Nitrogen has become a standard part of modified atmosphere packaging across the food industry, extending product shelf life without affecting quality. While the process is well established, introducing an inert gas into an enclosed production area also introduces a risk that deserves equal consideration during the design stage: oxygen depletion.

A recent installation carried out by Shawcity at a UK cheese manufacturer illustrates how oxygen depletion is addressed through engineering controls. The company was introducing new Nitrogen lines into their packaging areas that would be used during the sealing process. As part of the project, the customer wanted reassurance that any leak from the newly installed pipework could be detected quickly, protecting operators working in the vicinity while supporting normal production.

The design, based on the customer’s risk assessment, comprised two independent oxygen monitoring systems, one for each packaging area. Each system incorporated oxygen sensors, audible and visual alarms, and relays linked to external solenoid valves controlling the nitrogen supply. Should oxygen levels fall below the defined alarm threshold, the system not only alerts personnel but also isolates the nitrogen supply by automatically closing the appropriate valve. This approach reduces reliance on manual intervention and limits the duration of any gas release.

One of the key aspects of the project was that the monitoring system was introduced alongside the installation of new nitrogen pipework on an existing packaging line. Considering gas detection at the same time as process modifications helps ensure safety measures are integrated from the outset and can reduce the need for disruptive retrofits later.

Food manufacturing presents its own engineering considerations. Ventilation strategies are typically based on extraction rather than introducing air into hygienically controlled environments, meaning oxygen monitoring becomes an important component of the overall risk reduction strategy where inert gases are used. Separating the installation into two independent monitoring zones also reflected the operational layout of the facility, ensuring each packaging area could be managed without unnecessarily affecting the other.

Although this project centred on cheese packaging, the lessons extend across the wider food sector. Wherever nitrogen or other inert gases are used, the combination of risk assessment, continuous oxygen monitoring and automatic isolation should be considered alongside process design. Treating these measures as integral engineering controls, rather than optional additions, provides a more resilient approach to protecting personnel working in food production environments.

Shawcity’s fixed gas detection specialists can help assess and support projects from initial design through to installation, commissioning and ongoing maintenance.